by Michele Chabin, Special for USA TODAY

by Michele Chabin, Special for USA TODAY

JERUSALEM â?? People in southern Israel waited to see whether an uneasy calm would last after they hid in bomb shelters to get away from the heaviest Palestinian rocket fire since 2012.

The Palestinian terror group Islamic Jihad announced Thursday that it would observe a cease-fire after launching 60 rockets at Israel, which prompted the Israeli Defense Forces to attack "terror" positions inside Gaza, a territory controlled by the anti-Israel group Hamas.

After Islamic Jihad's announcement, rockets were fired at southern Israel on Thursday evening. One was intercepted by anti-missile batteries.

The violence shattered a truce Israel and Hamas made in November 2012 after more than a week of intense fighting and has set Israelis on edge.

In Sderot, an Israeli town near the Gaza border that has weathered hundreds of rocket attacks over the past decade, Mayor Alon Davidi said the city's residents are prepared.

"Sderot is prepared emotionally and in terms of security," Davidi said. "The residents of Sderot are backing the government. When you see rockets explode and after that, the IDF responds, you realize that it is important to the country."

Wednesday, Israelis near the Israel-Gaza border headed for shelters when Islamic Jihad launched its barrage. Thursday morning, air raid sirens sounded in Ashkelon and Ashdod, two Israeli coastal cities in the south, to alert people to more rockets.

Islamic Jihad said the rocket attacks were retaliation for Israeli "provocations" and violations of a cease-fire, including an airstrike that killed three Islamic Jihad members this week.

Thursday, senior Islamic Jihad official Khaled al-Batch said Egypt "initiated contacts with us in the past few hours. We agreed to restore the calm. As long as the occupation (Israel) honors the calm, we will honor the calm, and instructions are being given right now to al-Quds brigades, our military wing, about this understanding."

Hamas official Ghazi Hamad said Hamas had not been officially notified of the agreement.

Terri Davis, a resident of Ashkelon, said the timing of the rockets was particularly difficult because of festivities leading up to Purim, a carnival-like Jewish holiday that begins Sunday night. Children all over the country hold parties and fairs the week before the holiday.

Davis said air raid sirens began to wail Thursday morning during a Purim party at her synagogue's preschool.

"When we heard the sirens, 70 children and 15 adults crowded into the shelter," she said. "The children, who were dressed in costumes, had been happy and singing when the siren went off, and I saw panic in their eyes. But the teachers and soldiers who had come for the party kept the children calm, singing and dancing."

Adele Raemer, who lives on Kibbutz Nirim, about a mile from the Gaza border, said residents were alerted to the cross-border tensions only after they heard a very loud explosion from a rocket that hit a field around 5 p.m.

"There was no warning, no red alert," Raemer said, referring to the system that warns residents near the border of imminent attack. "The windows shook. My son and I and our two dogs ran into my shelter."

Parents at the kibbutz received messages that their children, who ordinarily would have been returning home following after-school activities, were being kept at a safe place.

Raemer, who moved to the kibbutz 40 years ago, said the hostilities cause distress on both sides of the border.

"I'm sure the man on the street in Gaza just wants to put bread on his table and have his kids go to school and come home safely," Raemer said. "Unfortunately, the people of Gaza haven't been able to [stop] the Iranian-backed backed organizations that are making their lives as miserable, if not more miserable, than ours."